HYDROCHLORIC ACID 463
ammonia. It not infrequently contains a trace of arsenic, derived from
sulphuric acid used in generating it. The acid of the British Pharmacopoeia
is a colourless fuming liquid, containing not less than 35 per cent and not
more than 38 per cent of hydrochloric acid "by weight. Acidum hydro-
chloricum diluturn is an official preparation -which contains 10 per cent of
hydrochloric acid by "weight. The dose is 10 to 120 minims.
Special Symptoms. — It is less active than the other two acids. Hence
the symptoms produced by it are much milder. It does not stain the skin or
mucous membrane, but stains dark cloth reddish-brown. Salivation, con-
vulsions, delirium and paralysis of the limbs have occurred as special
symptoms in some cases.
The fumes of the acid, when inhaled, cause great irritation of the air
passages. Those who are constantly exposed to the fumes of this gas suffer
from chronic poisoning. It is characterized by coryza, conjunctivitis,
pharyngitis, laryngitis and bronchitis. It also causes nausea, vomiting and
epigastric pain, and produces inflammation of the gums and loosening of the
Fatal Dose. — The usual fatal dose is four drachms of the concentrated
acid. The smallest dose that has proved fatal to a girl, 15 years old, is one
drachm. Recovery has taken place after swallowing one ounce and a half
in one case and two ounces in another.
Fatal Period. — The usual fatal period is from eighteen to thirty hours.
A male child, ten weeks old, died in ten minutes after he was given a tea-
spoonful of crude hydrochloric acid.11 In a case recorded by Christensen 12:
death occurred in one hour and a half after a dose of about 200 cc.
hydrochloric acid. Death has also occurred in two hours, and has been
delayed for several days.
Post-mortem Appearances. — The mucous membranes acted on by the
acid are usually ash-grey, or black in colour interspersed with erosions.
The stomach wall is red owing to acute gastritis. Perforation, though rare,
was found to an extent of 18 mm. in diameter in the greater curvature of the
stomach of the male child who died in ten minutes as mentioned above.
There was also an ulcer, 10 mm. in size in the lesser curvature with brown-
black edges and red undersurface.
Chemical Analysis.-^-It should be remembered that this acid is found in
a free state to an extent of 0.2 per cent or more in the gastric juice. Hence
the detection of a minute quantity hi the stomach contents is no proof of
poisoning by this acid, unless distinct marks of its chemical action are seen
in the throat and stomach. It may be, recovered from vomit by distillation,
and should then be tested by the f ollowing tests : —
1. A solution of silver nitrate produces a heavy, curdy, white precipi-
tate of silver chloride, insoluble in excess or in strong nitric acid, but soluble
in ammonium hydroxide or potassium cyanide. The white precipitate
becomes grey on exposure to sunlight.
2. If heated with manganese dioxide, chlorine gas is evolved, known by
its greenish-yellow colour, irritating smell and bleaching action on vegetable
3. When brought near ammonia, white fumes of ammontea
are given off.
11. D. Sdiranz, Dewt. Z. ges. S«r, $fecl» Łaru 1938, XXX, 327; The
Criminal. Bet?., April, Vol. VH* Fart H* 1939, p. m
12. Ugesfarijt /or Lcceger, Copenfea^ii, Jan, 26, 1928, p. 8S ; Jour.
31, 1:928, p. 108& *